File Change Semantics

Origin. Irene Heim, The Semantics of Definite and Indefinite Noun Phrases (PhD dissertation, University of Massachusetts Amherst, 1982), chapter 3; "File change semantics and the familiarity theory of definiteness" (in Bäuerle, Schwarze, and von Stechow, eds., Meaning, Use, and Interpretation of Language, de Gruyter, 1983); and "On the projection problem for presuppositions" (WCCFL 2, 1983). Hans Kamp's DRT (1981) reached an equivalent system independently. The immediate ancestor is Lewis, "Adverbs of quantification" (1975), from which Heim takes the claim that indefinites are not quantifiers but open formulas bound by whatever operator is around; Stalnaker's common ground is the pragmatic ancestor.

Models. The context is a file: a record of which discourse referents are in play together with what has been said about them. Interpreting a sentence is updating that record, so a meaning is a file change potential rather than a truth condition. Formally a file F is a pair of its domain — the indices currently in use — and its satisfaction set, a set of pairs of a variable assignment and a world. Truth is recovered afterwards: the content of F is the set of worlds w for which some assignment g has ⟨g, w⟩ in the satisfaction set. Definiteness is not uniqueness but familiarity, a condition on whether the index is already in the domain.

Formalism.

File: F = ⟨Dom(F), Info(F)⟩. Dom(F): set of discourse referents (cards). Info(F): conditions on referents.

File as satisfaction set: Sat(F) ⊆ {⟨g, w⟩ : g an assignment, w a world}. Dom(F): the indices g is required to fix. Content(F) = {w : ∃g ⟨g, w⟩ ∈ Sat(F)}. F is true in w iff w ∈ Content(F).

Context: Set of files. Represents possible ways discourse can be. Updates refine.

Indefinite (a/an): "A man" introduces new card. Fresh discourse referent. Adds to domain. Novel.

Definite (the): "The man" requires existing card. Presupposes familiarity. Must be in Dom(F). Anaphoric.

Update (indefinite): ⟦a man⟧(F) = F' where: Dom(F') = Dom(F) ∪ {x}. Info(F') = Info(F) ∪ {man(x)}. Extends file.

Anaphora: Pronouns pick existing referents. "He" selects card from Dom(F). Resolution from file.

Felicity: Context F appropriate for φ if: Presuppositions of φ satisfied in F. Definites have antecedents.

Novelty/Familiarity: Indefinites: novel (not in Dom). Definites: familiar (in Dom). Heim's condition.

Indefinites are not quantifiers: An indefinite contributes an open formula with a free index. Existential force comes from default existential closure at the text level. Under an adverb of quantification the index is bound by that adverb instead. Lewis (1975): "usually", "always", "never" bind whatever variables are free.

Tripartite structure: Operator + restrictive clause + nuclear scope. "If a farmer owns a donkey, he beats it" — the if-clause is the restrictor. The universal force is the operator's, not the indefinite's. Donkey anaphora falls out.

Presupposition as definedness: F + φ is defined only if F entails the presuppositions of φ. F + (φ ∧ ψ) = (F + φ) + ψ, so φ can satisfy ψ's presupposition. F + (φ → ψ) evaluates ψ in F + φ. Karttunen's filters are consequences of these clauses, not extra rules.

Relation to DRT: Similar dynamics. Files ≈ DRSs. Different presentation. Both dynamic binding.

Symbols.

Symbol	Unicode	Name	Meaning
⟦α⟧	—	Interpretation	The file change potential of α
∪	U+222A	Union	Extension of a file's domain or information
∈	U+2208	Element of	Membership in a domain or satisfaction set
⊆	U+2286	Subset	Sat(F) is a set of assignment–world pairs
∃	U+2203	Existential quantifier	Existential closure recovering content
∧	U+2227	Conjunction	Sequential update in the projection clauses
→	U+2192	Conditional	Consequent evaluated in the updated context
φ, ψ	U+03C6, U+03C8	Phi, psi	Sentence metavariables
⟨	U+27E8	Angle bracket, left	Opens the pair ⟨g, w⟩ or ⟨Dom, Info⟩
⟩	U+27E9	Angle bracket, right	Closes the pair
F	—	File	The context: a domain plus a satisfaction set
Dom(F)	—	Domain	The indices in play; the file's cards
Info(F)	—	Information	What has been said of the referents
Sat(F)	—	Satisfaction set	Assignment–world pairs verifying the file
x	—	Discourse referent	An index on a noun phrase
g, w	—	Assignment, world	Components of a satisfaction pair

Metatheory. Files are sets of assignment–world pairs, so truth is a derived notion — the content of a file is the set of worlds some assignment verifies — and the theory is expressively equivalent to first-order logic, with satisfiability accordingly undecidable. The substantive claim is Lewis's: indefinites are open formulas with no quantificational force of their own, receiving it from an adverb of quantification or, by default, from existential closure at the text level, which is what yields the universal reading of the donkey indefinite without positing an ambiguity. Heim (1983) obtained the projection result the framework is best known for: with presupposition treated as a definedness condition on the update and the connectives defined so that each conjunct or antecedent updates the context for what follows, Karttunen's inventory of plugs, holes, and filters is derived rather than stipulated. Heim later noted that files and Kamp's boxes are notational variants; Groenendijk and Stokhof (1991) supplied the compositional, representation-free reformulation.

Applies to. Donkey anaphora. Definiteness and indefiniteness. Discourse anaphora and antecedent accessibility. Presupposition projection. Dynamic semantics. Discourse processing in computational linguistics.

Limitations. Unselective binding overgenerates. "Most farmers who own a donkey beat it" quantifies over farmer–donkey pairs, so a single farmer with many donkeys distorts the proportion — a wrong prediction, and the reason Heim herself (1990) abandoned unselective binding for an E-type analysis. The same mechanism cannot generate the weak reading of donkey sentences alongside the strong one. The Novelty–Familiarity Condition is not predictive without accommodation: "the sun" and bridging definites have no antecedent card, so a repair rule does the work the condition was supposed to do, and nothing constrains when the repair is available. The projection derivation is order-sensitive, which makes conjunction non-commutative, and it inherits the proviso problem — a conditional presupposition is predicted where an unconditional one is heard. Construction operates on indexed logical forms rather than on surface syntax, so the original theory is representational, not compositional.